Achaeometrical Research in Hungary II., 1988

BIBLIOGRAPHY - SUMMARIES - DATING

ages estimated on the basis of calibration curves was considered the Age of the fossil samples. Csapó J., Tóth-Pósfai L, Csapó-Kiss Zs.: Separation of D- and L-amino acids by ion exchange chromatography in the form of 2-sulfonic acid alanyi dipeptides = Amino Acids (1990)96-101. A method of ion exchange column chromatography was developed for the determination of D- and L-amino acids in the form of diastereoisomer dipeptide. First the protein containing samples were hydrolysed with 6 mole hydrochloric acid then the single amino acids were separated in an LKB automated amino acid analyser with the LKB fraction collector. Following lyophilization the single amino acids were transformed with (tBOC)2-L-CySS-(ONSu)2 active ester into 2 sulfonic acid-alanyl dipeptide after inserted oxidation by performic acid. The 2-sulfonic acid-alanyl dipeptides appear on the chromatogram directly after cysteic acid. They separate easily from one another and from the cysteic acid formed from the excess of active ester. Accuracy of the determination is satisfactory. The coefficient of variation amounts to 4-10%. The use of the method is suggested to laboratories having an amino acid analyser and wish to determine D- and Lamino acids in synthetic amino acids complements, peptides or natural materials. Csapó J., Tóth-Pósfai L, Csapó-Kiss Zs.: Separation of D- and L-amino acids by ion exchange column chromatography in the form of alanyi dipeptides = Amino Acids (1991) 1.331-337. A method of ion exchange column chromatography was developed for the determination of D- and L-amino acids in the form of diastereoisomeric dipeptide. First the protein containing samples were hydrolysed with 6 molar hydrochloric acid, then the single amino acids were separated in an LKB automated amino acid analyser with the LKB fraction collector. Following lyophilization, the single amino acids were transformed into alanyi dipeptides with tertiary-butyloxycarbonil-L-alanine-N-hydroxy-succinimide (tBOC-L-Ala-ONSu) active ester. The alanyi dipeptides were easily separated from one another and the initial amino acids. Determination of the D- and L-amino acids in This form is relatively accurate and reproducible but takes some time (33-38 min). Accuracy of the determination is satisfactory. The coefficient of variation amounts to 3-5%. The use of the method is suggested to laboratories having an amino acid analyser and wish to determine D-and L-amino acids in synthetic amino acids complements, peptides or natural materials. Csapó J., Némethy S., Folestad, S., Tivesteii, A., Martin, T. G., Csapó-Kiss Zs.: Age determination based on amino acid Racemization. A new possibility = Amino Acids (1994)7.317-325. A method has been developed to determine the Age of fossil bone samples based on amino acid Racemization (AAR). Approximately one hundred fossil bone samples of known Age from Hungary were collected and analysed for D- and L- amino acids. As the Racemization of amino acids is affected by temperature, pH, metal content of the Soil, and time passed since death, These factors were eliminated by comparing the estimated Age to Age determined by the radiocarbon method. Determining the D- and L- amino 278